1. Field of the Invention
The present invention relates to a sound muffling device for an air conditioning unit. More specifically, the present invention is directed to a device for muffling the sound produced by rain or dripping water hitting the housing of an air conditioner.
2. Description of the Related Art
Air conditioning units are ubitiquously utilized for ventilating and cooling air in houses, apartments and other types of residences. In modern residences, air conditioning units typically include a central air conditioning system integrated within the residence. However, older residences, apartment buildings and office buildings without such an integrated central air conditioning system generally use one or more wall-mounted air conditioning units for cooling air inside the residence. The wall-mounted air conditioning unit includes a housing that fits within an opening through the wall or through a partially open window and extends beyond the side of the outside of the residence or building.
One problem associated with wall-mounted air conditioning units occurs when water droplets fall on the upper surface of the air conditioning unit housing. Although rainfall is the most common source of water droplets, in multi-story buildings water droplets may also fall from the condensate produced by another air conditioning unit disposed above the air conditioning unit housing. The impact of these water droplets whether raindrops or drops of air conditioner condensate falling on the upper surface of the air conditioning unit housing creates a repetitive, irritating noise that can be heard from inside the building. This noise often is sufficiently irritating and disturbing to keep residents of the building awake.
Previous attempts have been made to muffle the sound of water during rainfall. U.S. Pat. No. 5,386,702 to Weisen discloses a synthetic sponge or other resilient material that is secured to the top of the air conditioner for absorbing the physical impact of rain and water droplets that would otherwise impinge on the air conditioner unit housing. However, such sponge or resilient material quickly loses its effectiveness. Once a sufficient amount of water is absorbed into the material.subsequent water droplets will bounce off the water or rain-soaked material to create noise.
U.S. Pat. No. 5,159,789 to Haapanen discloses a noise baffle for reducing noise in a rain gutter system. However, the noise baffle is limited to reducing noise associated with a stream of water previously collected in a main gutter and flowing in one or more downspout sections of the rain gutter system and is-thus inapplicable to air conditioning units. A need thus exists in the art for a device that improves the muffling of sound associated with wall-mounted air conditioning units.
The present invention is directed to a device for muffing the sound of water droplets falling onto an upper surface of the housing of an air conditioning unit that extends beyond the side of a building. The sound muffling device comprises a plurality of screens of different fineness of mesh, and a frame for holding the plurality of screens arranged in a progressively finer parallel spaced-apart relationship. The device is secured to the housing of the air conditioning unit with the finest mesh screen closest to and in parallel relation with the upper surface of the housing.